1. Field of Invention
The present invention relates to fault detection for electric circuits and electronic devices. More particularly, the present invention relates to subject matter that fault can be detected by measuring resistance or impedance value.
2. Description of Related Art
Begin from the first invention of integrated circuit in 1960, the number of electronic devices on a chip has been increased in an explosive rate. The function, capacity, and operational speed of the integrated circuits have been greatly improved with the progress of the semiconductor integrated circuits has step into ULSI (ultra large scale integration) or even higher level. The capacity of a single semiconductor chip is increased from several thousands to hundreds of millions, or even billions of devices. Thus, functional inspection and quality control for manufactured chips with such highly integrated circuits have become quite important processes to ensure chip operation and reliability.